There should be some structure in mangrove swamps

There should be some shack named smth like "Shady Shack" and during the night there should be some blind Witch-like mob(friendly) inside the shack that would allow us to get some random ahh items.
Items could be smth like "Splash potion of fear" and when you throw it on mobs, the mobs can like run away from you. It could also be brewed with smth like "Mangrove root".